Polyclonal Bcell Lymphoproliferative Disorder

An entity called polyclonal hairy B-cell lymphoprolifer-ative disorder (HBLD) has been described in Japan.7273 All of the patients were females, had splenomegaly and minimal or no lymphadenopathy; persistent lympho-cytosis was noted in all the patients, some having anemia and thrombocytopenia. Abnormal lymphocytes present in the peripheral blood and bone marrow had round nuclei and abundant pale cytoplasm with long microvilli and prominent membranous ruffles. They expressed CD5- CD10- CD11c+ CD19+ CD20+ CD23 - by flow cytometry studies. Although these findings were similar to those of HCL, the surface marker of the kappa and lambda chains was unbiased and studies of immunoglobulin gene rearrangements and expressions showed a polyclonal proliferation of B cells.73